<?php
// // users (id, name, gender, age)
// delete from users where id = 1;

$dsn = 'mysql:host=localhost;dbname=phpcode20;charset=utf8';
$pdo = new PDO($dsn, 'root', '123456');

$sql = 'delete from users where id = 4';

$result = $pdo->exec($sql); // === false
var_dump($result);
